Precast concrete deck slab



FIG. 1 is an isometric view of a precast concrete deck slab, showing my new design;

FIG. 2 is a front side view thereof, the back side being a mirror image;

FIG. 3 is a top plan view thereof; and,

FIG. 4 is a right side view thereof, the left side being a mirror image. 

The ornamental design for a precast concrete deck slab, as shown and described. 